The connecting process dissimilar metals has been carried, the example used the resistance spot welding method. However, the welding prosess requires resistance on both sides of the material to be joined. As an alternative, connecting materials can be used spot TIG welding method. Spot TIG welding is a new method of developing TIG welding machines so that it can be used to do spot welding. The purpose of this study is to determine the effect of welding current variations on microstructure, hardness, and shear strength on the joints results of spot TIG welding dissimilar materials. The material used in this study is a low carbon steel plate and aluminum 1100 with a thickness of 0.8 mm each plate. Each plate material is cut to a length 10 cm and a width 3 cm which is then joined with position of low carbon steel material at the top. The welding process uses holding time 5 second. The welding current parameters used in this study were 100 A, 110 A, 120 A and 130 A. The testing conducted in this study are metallografi testing, hardness testing and tensile strength testing. Based on the results of the research, the weld metal area of low carbon steel the structure become roughter and the weld metal area of aluminum shows the equiaxed dendritic and columnar dendritic structures. The highest hardness value of the welded joint area is found in weld metal area of low carbon steel with variation current 120 A of ± 208 HV. While the highest average shear strength was found in the variation welding current 100 A of 37.65 N / mm².